/Engine/Plugins/FX/Niagara/Source/Niagara/Classes/NiagaraEmitterHandle.h
Sets whether or not this emitter is enabled within the System. Disabled emitters aren't simulated. Returns whether or not the enabled state changed.
bool SetIsEnabled ( bool bInIsEnabled, [UNiagaraSystem](API\Plugins\Niagara\UNiagaraSystem) & InOwnerSystem, bool bRecompileIfChanged )